反应详情

A mixture of 2-[3-[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]phenyl]propyl]-1,3-dioxane (2.0 g), 2,4-oxazolidinedione (0.99 g), piperidine (0.21 g) and acetic acid (50 ml) was heated for 24 hours under reflux. The reaction mixture was concentrated under reduced pressure, to which was added ethyl acetate. The ethyl acetate layer was washed with an aqueous solution of sodium hydrogencarbonate, 2N HCl and water, successively, which was then dried (MgSO4), followed by concentration. The concentrate was purified by means of a silica gel column chromatography. From the fractions eluted with chloroform-ethyl acetate (5:1), 5-[4-[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]phenyl]butylidene]-2,4-oxazolidinedione (0.55 g, 26%) was obtained. Recrystallization from ethyl ether-methanol gave colorless needles, m.p.152-153° C.

1. temperaturewas heated for 24 hours
2. temperatureunder reflux
3. concentrationThe reaction mixture was concentrated under reduced pressure, to which
4. additionwas added ethyl acetate
5. washThe ethyl acetate layer was washed with an aqueous solution of sodium hydrogencarbonate, 2N HCl and water
6. dry with materialsuccessively, which was then dried (MgSO4)
7. concentrationfollowed by concentration
8. customThe concentrate was purified by means of a silica gel column chromatography
9. washFrom the fractions eluted with chloroform-ethyl acetate (5:1)