N-Methylacetamide → HCID 22865001, compound

Temperature

-78 °C

Under a nitrogen atmosphere, a solution of N-methylacetamide (116 μl, 1.52 mmol) in tetrahydrofuran (2 ml) and then hexamethylphosphoric triamide (555 μl, 3.19 mmol) were dropwise added at -78° C. to a solution comprising 2.0M lithium diisopropylamide--tetrahydrofuran (1.6 ml, 3.19 mmol) and tetrahydrofuran (10 ml). The mixture was stirred at -78° C. for 30 minutes. Then, a solution of (2S,4R)-N-tert-butoxycarbonyl-4-tert-butyldimethylsiloxyprolinal (500 mg, 1.52 mmol) in tetrahydrofuran (2 ml) was dropwise added. The reaction mixture was stirred at room temperature for 2 h. Water was added to the reaction mixture. Then, the reaction mixture was poured into a mixture of ethyl acetate-water. The organic layer was washed with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate, and concentrated in vacuo. The obtained oily residue was subjected to silica gel column chromatography (chloroform--methanol=20:1) to give the title compound (158 mg, yield: 25.9%).

1. stirringThe reaction mixture was stirred at room temperature for 2 h
2. washThe organic layer was washed with saturated aqueous sodium chloride
3. dry with materialdried over anhydrous sodium sulfate
4. concentrationconcentrated in vacuo

ORD record

ord-1a583f2c104e472e8c9468e673d17c71

Source dataset

uspto-grants-1996_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05550121