Dimethyl Sulfoxide → Tert-butyl 3-oxopiperidine-1-carboxylate

Temperature

-78 °C

A mixture of DMSO (7.8 mL, 109.3 mmol) and methylene chloride (100 mL) was cooled to −78° C. Oxalyl chloride (4.8 mL, 54.7 mmol) was added to this solution via syringe. The mixture was stirred at −78° C. for 30 min. A solution of 3-hydroxypiperidine-1-carboxylic acid tert-butyl ester (10.0 g, 49.7 mmol) in methylene chloride (30 mL) was added dropwise to this solution (temperature remained below −70° C.). The mixture was stirred for 30 min. Triethylamine (28 mL, 200 mmol) was added dropwise over 20 min. The mixture was stirred at −78° C. for 1 h and was allowed to warm to room temperature and stirred for 45 min. The mixture was diluted with water, and the layers separated. The organic layer was washed with water, dried Na2SO4), filtered, and concentrated to give 3-oxopiperidine-1-carboxylic acid tert-butyl ester (10.2 g) as a yellow, brown liquid.

1. stirringThe mixture was stirred for 30 min
2. stirringThe mixture was stirred at −78° C. for 1 h
3. temperatureto warm to room temperature
4. stirringstirred for 45 min
5. customthe layers separated
6. washThe organic layer was washed with water, dried Na2SO4),
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-beda330daffa4deb8939c3eeec293710

Source dataset

uspto-grants-2006_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06992082B2