反应详情

Titanium tetrachloride(15.5 g) was added dropwise into a mixture of 4-(4-chlorophenyl)-4-oxazolin-2-one(4.00 g), ethyl chloroglyoxylate(5.58 g) and dichloromethane(30 ml) at room temperature. After stirring for 2 hours, the reaction mixture was poured into ice water, and extracted with ethyl acetate. The ethyl acetate layer was washed with water, and dried(MgSO4). The solvent was evaporated to give ethyl 2-[4-(4-chlorophenyl)-2-oxo-4-oxazolin-5-yl]-2-oxoacetate as crystals(5.38 g, 89%). This was recrystallized from ethyl acetate-hexane to give pale yellow prisms. mp 152-153° C.

1. extractionextracted with ethyl acetate
2. washThe ethyl acetate layer was washed with water, and dried(MgSO4)
3. customThe solvent was evaporated