反应详情

温度

-30 °C

To a mixture of 288 mg of cis-3-amino-2-oxoazetidine-4-carboxylic acid methyl ester, 4 ml of propylene oxide and 3 ml of N,N-dimethylacetamide, which is stirred previously under ice-cooling, is added dropwise 400 mg of 1H-tetrazol-1-yl acetyl chloride, followed by stirring for 30 minutes. To the mixture is added 50 ml of ethyl ether, followed by stirring under cooling at -30° C., and then the upper layer is removed by decantation. The lower layer is subjected to the same procedure as above twice, followed by addition of 10 ml of acetone. The resultant solution is developed and purified by column-chromatography on silica-gel (40 g, 3×10 cm) using a mixture of acetone:methylene chloride (1:1) as eluent, followed by drying to give 403 mg (84%) of cis-3-(1H-tetrazol-1-ylacetamido)-2-oxoazetidine-4-carboxylic acid methyl ester.

1. temperaturecooling
2. stirringby stirring for 30 minutes
3. stirringby stirring
4. customthe upper layer is removed by decantation
5. additionfollowed by addition of 10 ml of acetone
6. custompurified by column-chromatography on silica-gel (40 g, 3×10 cm)
7. additiona mixture of acetone:methylene chloride (1:1) as eluent
8. customby drying