反应详情

温度

102.5 °C

A mixture of methyl 3-[4-(3,4-dichlorophenyl)-2-oxo-4-oxazolin-5-yl]propionate (9.0 g), phosphorus oxychloride (26.2 g) and pyridine (2.25 g) was heated to 100-105° C. and stirred for 1 hour. The reaction mixture was added dropwise to heated water (100 ml) of 30° C. and extracted with ethyl acetate (150 ml×2). The organic layer was washed with a saturated aqueous solution of sodium chloride (100 ml), and dried over anhydrous magnesium sulfate. The organic layer was concentrated, the residue was subjected to silica gel column chromatography, and methyl 2-chloro-4-(3,4-dichlorophenyl)-5-oxazolepropionate was obtained as a yellow oil (5.00 g, 52%) from an ethyl acetate-hexane (1:4, v/v)-eluted fraction.

1. additionThe reaction mixture was added dropwise
2. extractionextracted with ethyl acetate (150 ml×2)
3. washThe organic layer was washed with a saturated aqueous solution of sodium chloride (100 ml)
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationThe organic layer was concentrated