反应详情

A mixture of 8-chloro-2,3-dihydro-3-hydroxy-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one (36.0 g), acetic anhydride (50 ml), dimethylsulfoxide (100 ml), pyridine (3 ml) and toluene (100 ml) is stirred at room temperature for 3 days. Water is added to the mixture, and the mixture is extracted with ethyl acetate, and the extract is washed with water, and dried. The resultant is evaporated to remove the solvent, and diethyl ether is added to the residue. The precipitated crystal is collected by filtration to give 3-acetoxy-8-chloro-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one (24.5 g).

1. extractionthe mixture is extracted with ethyl acetate
2. washthe extract is washed with water
3. customdried
4. customThe resultant is evaporated
5. customto remove the solvent, and diethyl ether
6. additionis added to the residue
7. filtrationThe precipitated crystal is collected by filtration