Dimethyl Sulfoxide → Benzyl 2-formylpyrrolidine-1-carboxylate

Temperature

0 °C

To a mixture of 10 mL CH2Cl2 and 2.1 mL oxalyl chloride at −78° C. was added a solution of DMSO (1.04 mL) in CH2Cl2 (3 mL) dropwise over 10 min while stirring. After the mixture was stirred for 10 min, a solution of the (S)-(+)-1-benzyloxycarboxy-2-pyrrolidinemethanol (1.5 g) in CH2Cl2 (4 mL) was added slowly over 10 min. The reaction mixture was then stirred at −78° C. for 1.5 h followed by the addition of 4.46 mL triethylamine. After stirring at −78° C. for 30 min, the mixture was warmed up to 0° C. and then stirred for 20 min at 0° C. To the mixture was added 1 mL of MeOH followed by addition of 8 mL of water. The aquous layer was separated and extracted with CH2Cl2 (3×60 mL). The combined organic layer was washed with NaHCO3, H2O and brine, successively, and dried (Na2SO4). Removal of the solvent provided 1.5 g of the title compound which was used directly for next step.

1. stirringAfter the mixture was stirred for 10 min
2. stirringThe reaction mixture was then stirred at −78° C. for 1.5 h
3. stirringAfter stirring at −78° C. for 30 min
4. stirringstirred for 20 min at 0° C
5. customThe aquous layer was separated
6. extractionextracted with CH2Cl2 (3×60 mL)
7. washThe combined organic layer was washed with NaHCO3, H2O and brine
8. dry with materialsuccessively, and dried (Na2SO4)
9. customRemoval of the solvent

ORD record

ord-e0aeb20d402f4980ab0fa4fe3526ba36

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06498165B1