反应详情

To the total amount of the product obtained in Example 2 was added 1.24 g of diethyl ethoxymethylenemalonate (XVI, Y=EtO, alkyl=Et, hereinafter abbreviated as EMME). The mixture was heated to 145° to 150° C. with stirring. After 1.5 hours, the system was evacuated to remove formed ethanol, and the mixture was heated a further 30 minutes with stirring under reduced pressure. After cooling, the product was isolated through silica gel column chromatography to yield 1.33 g of the titled compound, which has no tetrahydropyranyl moiety.

1. temperatureThe mixture was heated to 145° to 150° C.
2. customthe system was evacuated
3. customto remove
4. customformed ethanol
5. temperaturethe mixture was heated a further 30 minutes
6. stirringwith stirring under reduced pressure
7. temperatureAfter cooling
8. customthe product was isolated through silica gel column chromatography