反应详情

2 G (6.6 mmol) of 3-(3,5-di-t-butyl-4-hydroxybenzoyl)pyrrole were added to a cooled, stirred suspension of 0.70 g of sodium hydride (50% in mineral oil) in 50 ml of anhydrous dimethylformamide under nitrogen. After 30 minutes at room temperature, 0.7 ml of ethyl iodide was added, and stirring at room temperature was continued for an additional 2 hours. The reaction mixture was poured over a 10% HCl-ice mixture, then extracted three times with 250 ml ethyl acetate. The organic layer was washed five times with 200 ml water, dried and evaporated to dryness. The residue was purified by chromatography on alumina (3% water, 100 g) eluting with hexane:ethyl acetate (9:1). Crystallization from methylene chloride-hexane gave 1.11 g of N-ethyl-3-(3,5-di-t-butyl-4-hydroxybenzoyl)pyrrole (mp 73°-75° C.).

1. stirringstirring at room temperature
2. waitwas continued for an additional 2 hours
3. extractionextracted three times with 250 ml ethyl acetate
4. washThe organic layer was washed five times with 200 ml water
5. customdried
6. customevaporated to dryness
7. customThe residue was purified by chromatography on alumina (3% water, 100 g)
8. washeluting with hexane:ethyl acetate (9:1)
9. customCrystallization from methylene chloride-hexane