反应详情

An aqueous solution of 1N sodium hydroxide (34 ml) was dropwise added to an ethanol (50 ml) solution of methyl 2-chloro-4-(4-chlorophenyl)-5-oxazolepropionate (8.50 g), with cooling with ice. After stirring for 20 minutes with cooling and then for 30 minutes at room temperature, 2N hydrochloric acid was added thereto, and the crystals thus precipitated were collected by filtration to obtain 2-chloro-4-(4-chlorophenyl)-5-oxazolepropionic acid (8.00 g, 99%). This was recrystallized from ethyl acetate to give colorless prisms. mp 169-170° C.

1. temperaturewith cooling with ice
2. temperaturewith cooling
3. waitfor 30 minutes at room temperature
4. customthe crystals thus precipitated
5. filtrationwere collected by filtration