Tetrahydrothiopyran-4-one → HCID 21878144, compound

Temperature

-78 °C

A solution of 2-methylpropyl 4-bromophenylcarbamate (Step 1, 10.0 g, 36.7 mmol) in anhydrous tetrahydrofuran (184 mL) at −78° C. under N2 was treated n-butyllithium (1.6M in hexanes, 48.2 mL, 77.1 mmol) dropwise over 20 mins, and the mixture was stirred at −78° C. for 45 mins. The resulting slurry was then treated with a solution of tetrahydro-2H-thiopyran-4-one (4.48 g, 38.5 mmol) in anhydrous tetrahydrofuran (38 mL) dropwise over 5 mins to give an opaque mixture which was allowed to slowly warm to 0° C. with stirring over approximately 2.5 hrs. The mixture was then quenched by the slow addition of saturated aqueous ammonium chloride (75 mL), water (75 mL) was added, and the layers were separated. The organic phase was washed with water (50 mL) and saline (50 mL), dried over anhydrous magnesium sulfate and concentrated under reduced pressure, and the crude product was recrystallized from EtOAc/hexanes to give the title compound, mp 150-151° C.; MS (ESI−) for C16H23NO3S m/z 308 (M−H)−.

1. customto give an opaque mixture which
2. temperatureto slowly warm to 0° C.
3. stirringwith stirring over approximately 2.5 hrs
4. customThe mixture was then quenched by the slow addition of saturated aqueous ammonium chloride (75 mL), water (75 mL)
5. additionwas added
6. customthe layers were separated
7. washThe organic phase was washed with water (50 mL) and saline (50 mL)
8. dry with materialdried over anhydrous magnesium sulfate
9. concentrationconcentrated under reduced pressure
10. customthe crude product was recrystallized from EtOAc/hexanes

ORD record

ord-b80f9c7137c14c139e3a35310f9e72b4

Source dataset

uspto-grants-2006_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07049443B2