反应详情

To a mixture of ethyl 8-iodo-6-(trifluoromethoxy)-2-(trifluoromethyl)-2H-chromene-3-carboxylate prepared as in Example 21a, Step 2 (1.00 g, 2.07 mmole) and Pd(PPh3)4 (0.239 g, 0.207 mmole) in anhydrous toluene (50 mL) under a dry N2 atmosphere was added tributylallyltin (0.707 mL, 2.28 mmole). The mixture was refluxed for 16 h and 20% NH4F solution (50 mL) was added. The mixture was stirred for 1 h and extracted with EtOAc (200 mL). The extract was washed with brine (100 mL), dried over Na2SO4, filtered and concentrated in vacuo. Purification by silica chromatography (9:1 hexanes:EtOAc) gave 0.770 g (94% yield) of the product as a yellow oil: EIHRMS m/z 396.0769 (M+, C17H14F6O4, Calc'd 396.0796).

1. temperatureThe mixture was refluxed for 16 h
2. extractionextracted with EtOAc (200 mL)
3. washThe extract was washed with brine (100 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customPurification by silica chromatography (9:1 hexanes:EtOAc)