Dimethylformamide → HCID 54150686, compound

Participants

Reaction Steps

On the other hand, to a solution of 0.410 g of DMF in 10 ml of methylene chloride is added 0.475 g of diphosgene at -10° C. and the mixture is stirred at room temperature for 15 minutes. A solution of 1.23 g of 2-(2-chloroacetamidothiazol-4-yl)-2-isopropoxyiminoacetic acid (syn-isomer) and 0.530 g of triethylamine in 15 ml of methylene chloride is added dropwise at -60° to -50° C. and the mixture is stirred at -40°~-30° C. for 1.5 hours. Then, 0.490 g of triethylamine is added at -60°~50° C. and the above prepared THF solution is further added. The mixture is allowed to stand at room temperature over 1 hour and the solvent is distilled off under reduced pressure. The residual ethyl acetate solution is washed with water and concentrated under reduced pressure. Purifying the residue on a silica gel column (ethyl acetate: n-hexane=2:1) yields 1.23 g of (3S,4S)-4-acetoxy-3-[2-(2-chloroacetamidothiazol-4-yl)-2-isopropoxyiminoacetamido]-2-oxoazetidine (syn-isomer).

Provenance & Evidence