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 is treated n-butyllithium (1.6M in hexanes, 48.2 mL, 77.1 mmol) dropwise over 20 mins, and the mixture is stirred at −78° C. for 45 mins. The resulting slurry is 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 is allowed to slowly warm to 0° C. with stirring over approximately 2.5 h. The mixture is then quenched by the slow addition of saturated aqueous ammonium chloride (75 mL), water (75 mL) is added, and the layers are separated. The organic phase is washed with water (50 mL) and saline (50 mL), dried over anhydrous magnesium sulfate and concentrated under reduced pressure, and the crude product is 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 h
4. customThe mixture is then quenched by the slow addition of saturated aqueous ammonium chloride (75 mL), water (75 mL)
5. additionis added
6. customthe layers are separated
7. washThe organic phase is 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 is recrystallized from EtOAc/hexanes

ORD record

ord-017d5de7b1bd4dd1b1899d9e3a922acc

Source dataset

uspto-grants-2010_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07645781B2