反応 #5173

反応方程式

hydrochloric acid

(2S, 4R)-1-(t-butoxycarbonyl)-4-hydroxy-2-pyrrolidinecarboxylic acid

ethyl chloroformate

dimethylamine

→

title compound

(2S, 4R)-1-(t-Butoxycarbonyl)-2-(N,N-dimethylcarbamoyl)-4-hydroxypyrrolidine

溶媒

tetrahydrofuran

triethylamine

tetrahydrofuran

反応条件

後処理

1. 1
   workup.STIRRINGThe mixture was then stirred for 3 hours under ice cooling
2. 2
   workup.WAITto stand overnight at room temperature
3. 3
   抽出extracted with ethyl acetate
4. 4
   洗浄The extract was washed with an aqueous solution of sodium chloride
5. 5
   その他dried
6. 6
   その他The solvent was then removed by distillation under reduced pressure
7. 7
   その他the residue was purified by column chromatography through silica gel (
8. 8
   洗浄eluted with a 9:1 by volume mixture of ethyl acetate and methanol)

実験手順

3.84 ml of triethylamine was added, at -15° to -20° C., to a solution of 5.8 g of (2S, 4R)-1-(t-butoxycarbonyl)-4-hydroxy-2-pyrrolidinecarboxylic acid dissolved in 85 ml of dry tetrahydrofuran, and then a solution of 2.63 ml of ethyl chloroformate in 25 ml of dry tetrahydrofuran was added to the resulting mixture at the same temperature. The reaction mixture was then stirred for 2 hours, after which 19.75 ml of 50% by volume aqueous dimethylamine was added to it at -20° to -25° C. The mixture was then stirred for 3 hours under ice cooling, after which is was allowed to stand overnight at room temperature. At the end of this time, the mixture was poured into a mixture of 30 ml of concentrated hydrochloric acid and ice and extracted with ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried. The solvent was then removed by distillation under reduced pressure, and the residue was purified by column chromatography through silica gel (eluted with a 9:1 by volume mixture of ethyl acetate and methanol) to afford 429 mg of the title compound.

出典