反应详情

A mixture of 5-phenoxysalicylaldehyde (15.0 g, 70.0 mmol, see example 2d) and potassium carbonate (19.4 g, 140.0 mmol) in 250 ml of 1,4-dioxane is treated with acrolein (4.32 g, 77.0 mmol) under nitrogen. The mixture is heated at reflux for 6 hours. Water is added and the mixture is extracted with dichloromethane. The organic layer is dried (MgSO4) and evaporated. The residue is purified by flash chromatography (silica gel, 10% EtOAc/hexane) to give 6-phenoxy-2H-1-benzopyran-3-carboxaldehyde, as a fluorescent solid.

1. temperatureThe mixture is heated
2. temperatureat reflux for 6 hours
3. extractionthe mixture is extracted with dichloromethane
4. dry with materialThe organic layer is dried (MgSO4)
5. customevaporated
6. customThe residue is purified by flash chromatography (silica gel, 10% EtOAc/hexane)