反应详情

The starting material is prepared as follows: A mixture of 6-hydroxy-2H-1-benzopyran-3-carboxaldehyde (2.50 g, 14.2 mmol) and potassium carbonate (3.62 g, 38.4 mmol) in 50 ml of DMF is treated with 4-trifluoromethylbenzyl bromide (3.73 g, 15.6 mmol). The reaction is allowed to proceed overnight at room temperature. The mixture is diluted with water and extracted three times with dichloromethane. The combined organic layers are washed once with water, dried (MgSO4), and evaporated. Purification by silica gel chromatography (20% ethyl acetate/hexane) yields 6-(4-trifluoromethylbenzyloxy)-2H-1-benzopyran-3-carboxaldehyde, m.p. 108°-110° C.

1. customThe starting material is prepared
2. extractionextracted three times with dichloromethane
3. washThe combined organic layers are washed once with water
4. dry with materialdried (MgSO4)
5. customevaporated
6. customPurification by silica gel chromatography (20% ethyl acetate/hexane)