反应详情

To a solution of 4-[(5-ethyl-1H-pyrrol-2-yl)carbonyl]-benzonitrile (12.5 g) in N,N-dimethylformamide (63 mL) was added 60% sodium hydride in oil (2.68 g) in an ice-water bath under N2. After 30 minutes, to the mixture was added 1-(aminooxy)-2,4-dinitrobenzene (13.3 g). After 2 hours, the mixture was partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate. The combined organic layer was washed with water (100 mL) 3 times, 1N sodium hydroxide (100 mL), and brine, dried over magnesium sulfate, and evaporated in vacuo. The residue was purified by flash silica gel chromatography (silica gel, 500 mL) eluted with hexane-chloroform=1-2, 1-5, and 1-10 followed by triturated with isopropyl ether to give 4-[(1-amino-5-ethyl-1H-pyrrol-2-yl)carbonyl]benzonitrile (8.1 g, 60.7%) as an yellow solid. The mixed fraction and the mother layer (7 g) were repurified by flash silica gel chromatography (silica gel, 200 mL) eluted with hexane-chloroform=2-1 and 1-1 followed by triturated with isopropyl ether to give 4-[(1-amino-5-ethyl-1H-pyrrol-2-yl)carbonyl]benzonitrile (2.0 g, 15%) as a pale yellow solid.

1. waitAfter 2 hours
2. customthe mixture was partitioned between ethyl acetate and water
3. extractionThe aqueous layer was extracted with ethyl acetate
4. washThe combined organic layer was washed with water (100 mL) 3 times, 1N sodium hydroxide (100 mL), and brine
5. dry with materialdried over magnesium sulfate
6. customevaporated in vacuo
7. customThe residue was purified by flash silica gel chromatography (silica gel, 500 mL)
8. washeluted with hexane-chloroform=1-2, 1-5, and 1-10
9. customby triturated with isopropyl ether