Dimethyl Sulfoxide → 1-N-Cbz-3-pyrrolidinone

A dichloromethane (40 ml) solution of 16.58 ml (233.6 mmol) of dimethyl sulfoxide was added dropwise to a dichloromethane (200 ml) solution of 10.19 ml (116.8 mmol) of oxalyl chloride at −78° C., and the mixture was stirred for 10 minutes at the same temperature. To the reaction solution was added dropwise a solution of 23.50 g of literary known 1-benzyloxycarbonyl-3-hydroxypyrrolidine in 200 ml of dichloromethane at −78° C., followed by 60 minutes of stirring at the same temperature. This solution was mixed with 74.02 ml (531.1 mmol) of triethylamine at −78° C., and stirred for 60 minutes at the same temperature and then at room temperature for 60 minutes. After completion of the reaction, 500 ml of water was added dropwise to the reaction solution, and the organic layer was separated. The aqueous layer was washed with dichloromethane (100 ml×2), and combined organic layer was washed with saturated brine (300 ml×1). After drying the organic layer over sodium sulfate, the solvent was evaporated. The resulting residue was subjected to a silica gel column chromatography to yield 20.1 g (86%) of the title compound as an oily product from the eluate of n-hexane:ethyl acetate=1:1.

1. additionTo the reaction solution was added dropwise a solution of 23.50 g
2. customat −78° C.
3. waitfollowed by 60 minutes
4. stirringof stirring at the same temperature
5. stirringstirred for 60 minutes at the same temperature
6. waitat room temperature for 60 minutes
7. additionwas added dropwise to the reaction solution
8. customthe organic layer was separated
9. washThe aqueous layer was washed with dichloromethane (100 ml×2)
10. washwas washed with saturated brine (300 ml×1)
11. dry with materialAfter drying the organic layer over sodium sulfate
12. customthe solvent was evaporated

ORD record

ord-06ba330ac69643c298fcc080aa2fed00

Source dataset

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06469023B1