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

Temperature

-78 °C

To a solution of oxalyl chloride (28 mL, 56.2 mmol) in 14 mL dry CH2 Cl2 cooled at -78° C. (a dry ice acetone bath) was added 12 mL dry DMSO over 40 minutes. The reaction was stirred at -74° C. for additional 40 minutes and (S)-2-(hydroxymethyl)-1-pyrrolidinecarboxylic acid, 1,1-dimethylethyl ester, (5.40 g, 26.86 mmol) in 14 mL CH2 Cl2 was added dropwise at -65° C. over 30 minutes. The reaction stirred additional 20 minutes at room temperature and partitioned between Et2O and H2O. The Et2O layer was washed with more H2O (50 mL×4) and the H2O layers was extracted with Et2O (40 mL×3). All the Et2O layers was combined, washed with H2O, brine, dried over Na2SO4 and concentrated in vacuo. The crude product was isolated by a silica-gel column using EtOAc and hexane (1:5 ratio) as an eluting solvent to give title compound (84% yield).

1. stirringThe reaction stirred additional 20 minutes at room temperature
2. custompartitioned between Et2O and H2O
3. washThe Et2O layer was washed with more H2O (50 mL×4)
4. extractionthe H2O layers was extracted with Et2O (40 mL×3)
5. washwashed with H2O, brine
6. dry with materialdried over Na2SO4
7. concentrationconcentrated in vacuo
8. customThe crude product was isolated by a silica-gel column

ORD record

ord-cd18c3e6e70d41d3830de6d2049206fe

Source dataset

uspto-grants-1998_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05741799