反応 #215691

反応方程式

benzyl (2S,3S)-1-(3,4-dimethoxybenzyl)-2-[1 (R),2-dihydroxyethyl]-4-oxo-3-azetidinecarbamate

1,1'-carbonyldiimidazole

→

pure product

収率 96.5%

Benzyl (2S,3S)-1-(3,4-dimethoxybenzyl)-2-[(R)-2-oxo-1,3-dioxolan-4-yl]-4-oxo-3-azetidine carbamate

収率 96.5%

溶媒

THF

反応条件

後処理

1. 1
   温度under reflux for 4 hours
2. 2
   その他The THF was subsequently removed by concentration
3. 3
   洗浄washed once with 500 ml of 1N aqueous hydrochloric acid, twice with 1 l of water each time
4. 4
   乾燥once with 500 ml of saturated, aqueous sodium chloride solution and dried over magnesium sulphate with the addition of about 7 g of fuller's earth
5. 5
   その他The solvent was removed by concentration
6. 6
   その他After drying there

実験手順

215.23 g (0.5 mol) of benzyl (2S,3S)-1-(3,4-dimethoxybenzyl)-2-[1 (R),2-dihydroxyethyl]-4-oxo-3-azetidinecarbamate were dissolved in 3 l of THF at the boiling temperature. 12.61 g (0.75 mol) of 1,1'-carbonyldiimidazole were added. The mixture was boiled under reflux for 4 hours. The THF was subsequently removed by concentration, the oily residue was taken up in 1.5 l of dichloromethane, washed once with 500 ml of 1N aqueous hydrochloric acid, twice with 1 l of water each time and once with 500 ml of saturated, aqueous sodium chloride solution and dried over magnesium sulphate with the addition of about 7 g of fuller's earth. The solvent was removed by concentration. After drying there were obtained without further purification 220.3 g (yield: 96%) of pure product. M.p.: 135°-136° C.

出典