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

A solution of 3.4 ml of dimethylsulfoxide in 10 ml of methylene chloride was added to a solution of 2.0 ml oxalyl chloride in 50 ml of methylene chloride, maintained at -50° to -60° C., and immediately afterwards a solution of 3.74 g of (3R)-1-(t-butoxycarbonyl)-3-hydroxypyrrolidine in 20 ml of methylene chloride was added to the mixture over a period of about 2 minutes. The reaction mixture was kept stirred for 15 minutes at -50° to -60° C., and then 14 ml of triethylamine were added to it. The mixture was stirred at the same temperature for a further 5 minutes, and the stirring was then continued while allowing its temperature to rise to ambient. The reaction mixture was mixed with 100 ml of water and extracted with methylene chloride. The organic extract was washed with saturated aqueous sodium chloride solution and dried over anhydrous magnesium sulfate. The solvent was distilled off and the residue was chromatographed on a silica gel column, eluted with a 2/1 mixture of benzene and ethyl acetate, giving 3.61 g of 1-(t-butoxycarbonyl)-3-pyrrolidone as an oil.

1. temperaturemaintained at -50° to -60° C.
2. stirringThe mixture was stirred at the same temperature for a further 5 minutes
3. extractionextracted with methylene chloride
4. extractionThe organic extract
5. washwas washed with saturated aqueous sodium chloride solution
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationThe solvent was distilled off
8. customthe residue was chromatographed on a silica gel column
9. washeluted with a 2/1 mixture of benzene and ethyl acetate

ORD record

ord-1190462b07144183aa9db12074c85b2b

Source dataset

uspto-grants-1988_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04771046