反应详情

A solution of 2,2′-azobis(isobutyronitrile) (0.122 g), N-bromosuccinimide (3.19 g) and 4-(2-cyclopropylethoxy)-1-methyl-2-nitrobenzene (3.30 g) in ethyl acetate (100 mL) was refluxed for 8 hr. The reaction mixture was allowed to cool to room temperature, washed with saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The obtained solution was filtered with a short silica gel pad, and the filtrate was concentrated under reduced pressure. The obtained residue was dissolved in acetonitrile (150 mL), and molecular sieves 4A (10 g) and 4-methylmorpholine N-oxide (2.02 g) were added thereto at 0° C. The reaction mixture was stirred under a nitrogen atmosphere at room temperature for 3 hr, and concentrated under reduced pressure. The obtained residue was purified by silica gel chromatography (hexane/ethyl acetate) to give the title compound (1.90 g).

1. washwashed with saturated aqueous sodium hydrogen carbonate solution and saturated brine
2. dry with materialdried over anhydrous magnesium sulfate
3. filtrationThe obtained solution was filtered with a short silica gel pad
4. concentrationthe filtrate was concentrated under reduced pressure
5. dissolutionThe obtained residue was dissolved in acetonitrile (150 mL)
6. additionmolecular sieves 4A (10 g) and 4-methylmorpholine N-oxide (2.02 g) were added
7. customat 0° C
8. concentrationconcentrated under reduced pressure
9. customThe obtained residue was purified by silica gel chromatography (hexane/ethyl acetate)