Dimethyl Sulfoxide → tert-butyl (2S)-2-formylpyrrolidine-1-carboxylate

Temperature

-78 °C

At −78° C., a solution of dimethylsulphoxide (7.06 ml, 0.099 mol) in dichloromethane (10 ml) was added dropwise to a solution of oxalyl chloride (6.40 ml, 0.075 mol) in dichloromethane (15 ml). The reaction mixture was stirred for 20 min at −78° C. A solution of (S)-1-(tert-butoxycarbonyl)-2-pyrrolidinemethanol (10 g, 0.050 mol) in dichloromethane (50 ml) was added. The reaction mixture was stirred for 20 min at −78° C. Triethylamine (27.7 ml, 0.199 mol) was added. The reaction mixture was stirred for 10 min at −78° C. and then warmed to room temperature. It was washed with a 10% aqueous solution of sodium hydrogen sulphate (60 ml). The aqueous phase was extracted with dichloromethane (30 ml). The combined organic layers were washed with a saturated aqueous solution of sodium hydrogen carbonate (100 ml) and dried over magnesium sulphate. The solvent was removed in vacuo, to give 11.2 g of crude (S)-2-formylpyrrolidine-1-carboxylic acid tert-butyl ester, which was used for the next step without purification.

1. stirringThe reaction mixture was stirred for 20 min at −78° C
2. stirringThe reaction mixture was stirred for 10 min at −78° C.
3. temperaturewarmed to room temperature
4. washIt was washed with a 10% aqueous solution of sodium hydrogen sulphate (60 ml)
5. extractionThe aqueous phase was extracted with dichloromethane (30 ml)
6. washThe combined organic layers were washed with a saturated aqueous solution of sodium hydrogen carbonate (100 ml)
7. dry with materialdried over magnesium sulphate
8. customThe solvent was removed in vacuo

ORD record

ord-f0aa501273124621ae9954ab41f47b4d

Source dataset

uspto-grants-2006_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07101898B2