Water → 1-Benzyl-3,3-dimethylpiperidin-4-OL

A solution of 0.30 gm (1.3 mMol) 1-benzyl-2,4-dioxo-3,3-dimethylpiperidine in 5 mL tetrahydrofuran was stirred at room temperature as 2 mL (2 mMol) lithium aluminum hydride (2M in tetrahydrofuran) was added dropwise. The reaction mixture was then heated to reflux for 3 hours. The reaction mixture was then allowed to cool to room temperature. After stirring at room temperature for about 16 hours, the reaction mixture was cooled in an ice bath and treated sequentially with 0.5 mL water, 0.5 mL 5N sodium hydroxide, and 0.5 mL water with vigorous stirring. The resulting slurry was diluted with dichloromethane and anhydrous sodium sulfate was added. The slurry was filtered and the filter cake washed with dichloromethane. The combined filtrates were concentrated under reduced pressure and the residue subjected to silica gel chromatography, eluting with dichloromethane containing from 0-10% methanol containing 0.1% ammonium hydroxide. Fractions containing product were combined and concentrated under reduced pressure to provide 0.25 gm (88%) of the desired compound.

1. additionwas added dropwise
2. temperatureThe reaction mixture was then heated
3. temperatureto reflux for 3 hours
4. temperaturethe reaction mixture was cooled in an ice bath
5. additionwas added
6. filtrationThe slurry was filtered
7. washthe filter cake washed with dichloromethane
8. concentrationThe combined filtrates were concentrated under reduced pressure
9. washeluting with dichloromethane containing from 0-10% methanol containing 0.1% ammonium hydroxide
10. additionFractions containing product
11. concentrationconcentrated under reduced pressure

ORD record

ord-4f01b6f16a5a4e349bf838a54b83167f

Source dataset

uspto-grants-2005_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06881733B1