反应详情

3,5-Diacetyl-4,6-dihydroxy-2H-pyran-2-one (5.3 g.) is dissolved in 200 ml. of boiling toluene and an equimolar amount of p-chloroaniline is added. The mixture is refluxed for 12 hours, cooled and filtered to yield 5-acetyl-3-[1-(p-chlorophenylamino)ethylidene]-4-hydroxy-2H-pyran-2,6(3H)-dione, m.p. 205° -206° C.

1. temperatureThe mixture is refluxed for 12 hours
2. temperaturecooled
3. filtrationfiltered