Citric Acid → HCID 20741412, compound

Participants

Reaction Conditions

Reaction Steps

Under ice-cooling, triethylamine (725 μl) and methanesulfonyl chloride (341 μl, 4.40 mmol) were added to a dichloromethane (20 ml) solution of 4-(R)-[1-hydroxy-1-(thiazol-2-yl)methyl]-1-[1-(R)-phenylethyl]-2-pyrrolidone [F1] (1.21 g, 4.00 mmol), and the mixture was stirred at the same the temperature for 1 hour. The reaction solution was mixed with 10% citric acid (30 ml) under ice-cooling and extracted with chloroform (30 ml×2), and the organic layer was washed with saturated brine (100 ml) and then dried over anhydrous sodium sulfate. The solvent was evaporated under a reduced pressure, and the resulting residue was dissolved in N,N-dimethylformamide (30 ml), mixed with sodium azide (780 mg, 12.0 mmol) and then heated at 60° C. for 15 hours. After spontaneous cooling, the reaction solution was mixed with water (70 ml) and extracted with ethyl acetate (80 ml×3), and the organic layer was washed with saturated brine (200 ml) and then dried over anhydrous sodium sulfate. The solvent was evaporated under a reduced pressure, and the resulting residue was applied to a silica gel column chromatography. By eluting with a n-hexane:ethyl acetate system of from (1:2) to (1:3), 1.263 g (96%) of the title compound was obtained as a light yellow oil.

Provenance & Evidence